Hire car (4)
I believe the answer is:
taxi
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">hire car</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for taxi that I've seen before include "Cab for hire" , "Vehicle that plies for hire" , "Hackney cab" , "Motor cab" , "(Of a plane) move slowly on the ground" .)